People who suffer from cardiac or vascular diseases and patients that have undergone surgical procedures are at risk of developing blood clots that may result in life-threatening clinical conditions. Such people are often treated with blood-thinning anticoagulants and/or antiplatelet drugs. However, the amount of anticoagulant or antiplatelet agent(s) in the bloodstream must be maintained at the proper level; too little may result in unwanted clotting while too much can result in hemorrhaging. As a result, routine coagulation screening tests have been developed in order to evaluate the coagulation of blood, plasma, or other blood fractions.
Blood clotting is a complex process involving multiple initiators, activators, enzymes, and modulators where polymerization of fibrinogen ultimately leads to the formation of fibrin, which is a central constituent of a clot. Conventionally, the propensity or ability for blood to clot has been measured by determining the time taken for a sample of plasma or blood to clot. Clot formation may be detected visually, by observing the formation of fibrin, or by automated testing methods, such as photo-optical detection or changes in viscosity.
While such tests have proved useful to some extent, they suffer from a number of problems. For example, conventional test systems can be very expensive to operate and often require specialized instrumentation. Also, conventional test systems can be difficult to standardize and are often affected by abnormal conditions present in the blood being tested. Many conventional systems also only work well within narrow ranges of the clotting response being tested.
Thus, it would be desirable to provide a rapid and comprehensive method for assessment of the clotting activity of a fluid suspension that is quick, accurate, and cost effective.